CA2755155A1 - Spinal implant with a lockable patella link - Google Patents

Abstract

The invention relates to a spinal implant (100) comprising: - an anchor portion (110) to a vertebra, having first connecting means (112), and - a mounting part (120) comprising, on the one hand , internally an axial housing (151) for receiving transversely a connecting rod (30) this axial housing being delimited on the side of the anchoring portion (110) by a bottom (156), and on the other hand, second connecting means (140, 153) cooperating with said first connecting means to form a ball joint connection between said anchoring portion and said mounting portion. According to the invention, the spinal implant comprises retaining means (154) located near the bottom of the axial housing of said mounting portion, which are adapted to fix a locking element (130) in a fixed locking position wherein the ball joint formed by said first and second connecting means is locked to make said anchoring and fixed mounting portions rotatable relative to each other about at least two orthogonal axes.

Description

Spinal implant with locking ball joint connection TECHNICAL FIELD TO WHICH THE INVENTION REFERS
The present invention relates generally to implants spinal devices intended to immobilize at least two vertebrae one with respect to the other.
It relates more particularly to a spinal implant comprising:
an anchor portion to a vertebra, comprising first means liaison, and a mounting part comprising, on the one hand, internally a axial housing opening outwards by two lateral openings in look and in the form of cradles for transversely accommodating a connecting rod, this axial housing being delimited on the side of the anchoring part by a bottom, and, else second connecting means cooperating with said first means connection to form a ball joint connection between said anchoring portion and said mounting part.

BACKGROUND
Spinal implants of the aforementioned type are used in pairs and in combination with a connecting rod to treat osteoarthritis, fractures vertebrae or to correct deviations from the spine such that scoliosis or kyphosis.
To immobilize two vertebrae, a surgeon uses four implants spine, at a rate of two per vertebra. He commits to this effect their parts anchor in the vertebrae, then it secures the implants in pairs to means two connecting rods which each extend between two implants, one vertebra to the other. These two connecting rods are previously bent according to the correction to bring to the spine. In this way, both stems position parallel to the spine to maintain it sensibly right.
Two types of spinal implants are more particularly known. We known mono-axial implants in which the anchoring parts and mounting are aligned. In the majority of these implants, the anchor parts and are fixed relative to each other and are formed of a single room.
Some of these mono-axial implants, however, are arranged in such a way that their anchoring and mounting parts are connected to one another by a pivot connection around the longitudinal axis of the implant.
Polyaxial implants are also known in which the parts anchoring and mounting are connected to each other by a ball joint.

SUBSTITUTE SHEET (RULE 26)

2 Here is meant by a ball joint connection which allows the part of mounting to take different inclinations with respect to the axis of the part anchor. The anchoring and mounting parts are thus fixed in translation relative to each other along the three axes of space, but free in rotation around each of these three axes.
Moreover, a pivot link is understood to mean a link that allows the mounting portion to rotate around the anchor portion while remaining aligned according to this axis. The anchoring and mounting parts are thus fixed in translation Moon relative to each other along the three axes of space, fixed in rotation one by report to each other around two of these three axes, and free in rotation around the axis of the anchoring part.
The surgeon may have to use one or the other of these two types spinal implants, depending for example on the trauma to be treated and the shape of the patient's spine.
The disadvantage is that the implant manufacturer has to double its references to offer the surgeon the two types of spinal implants that him are needed to operate the patients.
The surgeon must manage the stocks of two types of implants and predict which type of spinal implant will be used before each operation.
An example of a polyaxial implant is presented in the document EP 1 869 606. As presented in this document, the implant comprises:
a screw whose head is partly spherical, a tubular receiving part comprising, on the side of its end low, an opening opening of the head of the screw, a tubular pressure element engaged inside the part of reception so that its low end bears against the head of the screw, whose high end forms a cradle for receiving a connecting rod, and a closure device comprising, on the one hand, an external bolt screwed into the upper end of the tubular receiving part in order to block the pressure element against the head of the screw so as to immobilize it, and, else an inner bolt screwed into the outer bolt to lock the rod of connection to the bottom of the cradle provided in the pressure element.
In this document, the locking means of the ball joint connection provided between the head of the screw and the reception opening of the receiving part tubular are therefore located above the home cradle of the connecting rod.
The disadvantage of this implant is that the ball joint can not be blocked only after the connecting rod has been engaged in the implant. The surgeon

3 so can not block it before operating the patient.
Document US 2007/0288004 discloses an implant spinal cord comprising:
a screw comprising a partially spherical head, a tubular tulip defining internally an axial housing which is intended to accommodate transversely a connecting rod and which has a part high threaded and a spherical lower part, - a rosette which is adapted to be housed in the spherical lower part of the tulip, - a bolt to screw into the tapping of the upper part of the tulip for block the connecting rod against the rosette, which has the effect of compressing this last in the spherical lower part of the tulip and thus immobilize the screw by compared to the tulip.
The rosette has a nipple adapted to engage in the imprint of the head of the screw, so that once the tulip is assembled to the screw, the implant himself features as a monoaxial implant. This rosette can also be replaced by another rosette devoid of a nipple, so that the implant can behave as a polyaxial implant.
However, in this document, the means allowing the head to pivot compared to the tulip and block the polyaxiality are carried by a alone and single piece, the rosette. As a result, to switch from a monoaxial implant to a polyaxial implant, it is necessary to remove the entire rosette, and so of dismantle the implant. The surgeon can not block the polyaxiality while the operation of the patient.

OBJECT OF THE INVENTION
The purpose of the present invention is to propose a spinal implant able to perform the function of a mono-axial implant as well as that of a poly-axial implant, in order to facilitate the surgeon's work and to avoid a duplication costs of manufacturing, storage and management of these implants.
For this purpose, it is proposed according to the invention a spinal implant such that defined in the introduction, which includes restraints that are located in a space between the bottom of the cradles formed by the two lateral openings and the bottom of the axial housing of said mounting part, and which are adapted to fix a locking element, distinct from the second means of connection, in a fixed locking position, in which the connection patella formed by said first and second connecting means is blocked for return said anchoring and mounting parts fixed in rotation with respect to

4 the other around at least two orthogonal axes.
Thus, thanks to the invention, in the absence of blocking element in position blocking, the implant behaves like a poly-axial implant. On the other hand, when a locking element is positioned in the locking position, the implant himself features as a mono-axial implant. Therefore, only one type of implants spinal cord allows the surgeon to treat all the trauma of the spine.
Thanks to the invention, the manufacturer and the surgeon have to manage only one reference of spinal implants.
Moreover, the surgeon can choose which type of implant he wants set up on the patient's spine during the operation surgery itself, to the benefit of the ease of use of this implant.
In particular, he can configure his implant in mono-axial mode is before the patient's operation, ie during the operation. He can even configure as well after engaging the anchoring part of the implant in the vertebral column of patient. He can also choose to keep the poly-axiality of his implant, of to immobilize the ball joint only at the end of the operation, when engages the connecting rod in the axial housing of the implant.
Other advantageous and non-limiting features of the implant spinal cord according to the invention are the following:
said retaining means are adapted to store an element of blocking in a fixed storage position, distinct from the position of blocking, in which the ball joint formed by said first and second means of connection is left free;
when the ball joint is locked, said anchoring and mounting are fixed relative to each other;
when the ball joint is locked, said anchoring and mounting are free to rotate around a single main axis, orthogonal said two orthogonal axes;
said anchoring portion comprising a threaded body extending in a direction first axis, and said axial housing extending along a second axis, the retaining means are arranged in such a way that they are able to fix said locking member in the locking position only when said second axis is coincident with said first axis;
said first connecting means comprise a head at least spherical portion and said second connecting means comprise a ring whose an inner face bears against said head;

said axial housing opens outwards through two openings side facing and in the form of cradles, and said ring has a face end which extends above the bottoms of the two lateral openings;
- said axial housing opens outwardly opposite the bottom by

An introductory opening, and said mounting portion includes, near said insertion opening, a thread which cooperates with a thread complementary to a locking screw for immobilizing said rod of liaison and said ball joint;
a blocking element adapted to cooperate with said retaining means for being fixed in said locking position;
said locking element belongs to said anchoring part;
the head of the anchoring part comprises two parts screwed one on the other, a first part of which constitutes said blocking element;
- the bottom which delimits the axial housing on the side of the anchoring part has an opening through which said axial housing opens towards outside this opening having a cylindrical portion which extends over a part spherical or conical, and said locking element, when in position of blocking, is located in contact with said cylindrical portion of the opening;
said locking element belongs to said mounting part;
said locking element is constituted by a ring;
said locking element and said anchoring part comprise stop faces which, when said locking element is in the position of blocking are in contact with or in close proximity to one another;
said mounting means comprising a body which comprises said bottom and which defines said axial housing, said retaining means come of forming with the body and said locking member has a face outer engaged in said retaining means;
said retaining means comprise a peripheral rib which extends into said axial housing, projecting from the inner face of the body who delimits this axial housing;
said retaining means comprise a thread which extends over the inner face of the body which defines said axial housing;
said mounting means comprising a ring engaged in said axial housing, said retaining means come from formation with said ring and said locking element has an outer face engaged in said retaining means.

6 DETAILED DESCRIPTION OF AN EXEMPLARY EMBODIMENT
The following description, with reference to the accompanying drawings, given in As a non-limitative example, it will make clear what is the invention and how it can be achieved.
In the accompanying drawings:
- Figure 1 is a perspective view of two vertebrae blocked one relative to each other using a connecting rod and two implants spinal according to the invention;
FIG. 2 is an exploded view of a first embodiment of one spinal implants of Figure 1;
FIG. 3 is a view in axial section of the spinal implant of the Figure 2, wherein the ball joint is left free;
FIGS. 4 and 5 are perspective views of the spinal implant of Figure 3, alone or equipped with a locking screw of the connecting rod;
FIGS. 6 to 8 are diagrams of operation of the blocking of, the spinal implant of Figure 2;
FIG. 9 is a view in axial section of the spinal implant of the Figure 2, wherein the ball joint is locked in pivot connection;
FIGS. 10 and 11 are perspective views of the spinal implant of Figure 9, alone or equipped with a locking screw of the connecting rod ;
FIG. 12 is an exploded view of a second embodiment of one spinal implants of Figure 1;
FIG. 13 is a perspective view of the spinal implant of the Figure 12 and a locking key;
FIG. 14 is a view in axial section of the spinal implant of the Figure 12, in which the ball joint is left free;
FIG. 15 is a view in axial section of the spinal implant of the Figure 14 and the locking key, in which the ball joint is locked in pivot connection;
FIG. 16 is an exploded view of a third embodiment of FIG.
one of the spinal implants of Figure 1;
FIG. 17 is a view in axial section of the spinal implant of the Figure 16, wherein the ball joint is left free;
FIG. 18 is a view in axial section of the spinal implant of the Figure 16, wherein the ball joint is locked in pivot connection;
FIG. 19 is an exploded view of a fourth embodiment of FIG.
one of the spinal implants of Figure 1;

7 FIG. 20 is a view in axial section of the spinal implant of the Figure 19, in which the ball joint is left free;
FIG. 21 is a view in axial section of the spinal implant of the Figure 19, wherein the ball joint is locked in pivot connection;
FIG. 22 is a view in axial section of the spinal implant of the Figure 19 and a locking tool for locking the ball joint;
FIG. 23 is an exploded schematic view of a fifth mode of performing one of the spinal implants of Figure 1;
FIG. 24 is a schematic perspective view of a tool for blockage of the spinal implant of Figure 23;
FIG. 25 is a view in axial section of the spinal implant of the Figure 23, in which the ball joint is left free; and FIG. 26 is a view in axial section of the spinal implant of the Figure 23, in which the ball joint is locked.
FIGS. 2 to 11, 12 to 15 and 16 to FIG.
18,19 to 22 and 23 to 26 five embodiments of a spinal implant 100;
200;
300; 400; 600.
As shown in these figures, the spinal implant 100; 200; 300;
400; 600 is a pedicle screw which has an anchoring portion 110; 210 ;
310; 410; 610 to anchor by screwing into the pedicle 21, 11 of a vertebra 10, 20, and a mounting portion 120; 220; 320; 420; 620 suitable for hosting a rod of liaison 30.
As shown in FIG. 1, such a connecting rod 30 allows, when it extends between two spinal implants 100 anchored to two vertebrae 20, to immobilize these two vertebrae 10, 20 relative to each other.
In the five embodiments of the spinal implant 100; 200;
300; 400; 600 (Figures 2, 12, 16, 19 and 23), the anchoring portion 110; 210;
310;
410; 610 has a screw shape, with a threaded body 111; 211; 311;

611 Al axis and, at the rear end of this threaded body, a head 112; 212 ; 312;
412; 612 having a reception fingerprint 116; 216; 316; 416; 616 of the end of a screwdriver. Here, this reception fingerprint 116; 216 ; 316;
416; 616 is a hexagonal imprint able to cooperate with an allen key.
In these five embodiments, the mounting portion 120; 220;
320; 420; 620 of the spinal implant 100; 200; 300; 400; 600 has a body 150; 250; 350; 450; 650 elongated, generally cylindrical around a axis A2.
This body 150; 250; 350; 450; 650 internally delimits a dwelling WO 2010/10319

8 PCT / FR2010 / 000142 axial 151; 251; 351; 451; 651 cylindrical of revolution around the axis A2. Of side of the anchor portion 110; 210; 310; 410; 610, this axial housing is delimited by a bottom 156; 256; 356; 456; 656. This axial housing 151; 251 351; 451; 651 opens out, behind the spinal implant 100 ; 200;
300; 400; 600, through an introduction opening 155; 255; 355; 455; 655.
he further opens forwards through an opening 153; 253; 353; 453;

provided in the bottom 156; 256; 356; 456; 656 of the body, in which is engaged the head 112, 212; 312; 412; 612 of the anchoring portion 110; 210;
310;
410; 610.
The body 150; 250; 350; 450; 650 is also equipped with two lateral openings 152; 252; 352; 452; 652 next to each other who extend in length parallel to the A2 axis and open at the rear of the spinal implant 100; 200; 300; 400; 600. The funds of these openings lateral 152; 252; 352; 452; 652, which extend forward of implant spinal 100; 200; 300; 400; 600, are rounded and thus present forms cradles. These two lateral openings 152; 252; 352; 452; 652 allow engaging the connecting rod 30 transversely in the axial housing 151;

351; 451; 651 of the body 150; 250; 350; 450; 650.
The spinal implant 100; 200; 300; 400; 600 also includes locking means 160; 260; 360; 460; 660 intended to cooperate with the body 150; 250; 350; 450; 650 to lock the connecting rod 30 in the body 150; 250; 350; 450; 650.
These locking means comprise a locking screw 160;
260; 360; 460; 660 having a threaded body 162; 262; 362; 462; 662 provided, recessed in its back face accessible to the surgeon, an impression of reception 161; 261; 361; 461; 661 of the end of a screwdriver.
Here, this reception fingerprint 161; 261; 361; 461; 661 is hexagonal and is fit at cooperate with a key allen.
The threaded body 162; 262; 362; 462; 662 of this locking screw 160; 260; 360; 460; 660 is adapted to be screwed into a tapping provided for in introductory opening level 155; 255; 355; 455; 655 from the accommodation axial 151; 251; 351; 451; 651 of the body 150; 250; 350; 450; 650 of the game of mounting 120; 220; 320; 420; 620.
When the locking screw 160; 260; 360; 460; 660 is screwed into this tapping, it sinks into the axial housing 151; 251; 351; 451;

to bear against the connecting rod 30 in order to block it in the body 150; 250; 350; 450; 650 of the mounting portion 120; 220; 320; 420;
620.

9 According to the embodiments shown in the different figures, as will be described in more detail later in this presentation, the part anchor 110; 210; 310; 410; 610 and the mounting portion 120; 220; 320 ;
420; 620 of the spinal implant 100; 200; 300; 400; 600 include respectively first and second connecting means cooperating together in such a way that the anchoring and mounting parts are linked together by a ball joint.
According to a particularly advantageous characteristic of the invention, the spinal implant 100; 200; 300; 400; 600 also includes means retainer 154; 245; 317; 454; 654 located near the bottom 156; 256;
356;
456; 656 of the body 150; 250; 350; 450; 650, which are suitable for fixing a element blocking 130; 230; 330; 430; 630 in a fixed locking position, in which the ball joint formed by said first and second means of bond is locked to make said anchor portions 110; 210; 310; 410; 610 and of mounting 120; 220; 320; 420; 620 fixed in rotation one with respect to the other around at least two orthogonal axes A3, A4 (see Figure 10).
The retaining means 154; 245; 317; 454; 654 are located in a space located between the bottom 156; 256; 356; 456 656 of the body 150; 250; 350 ;
450; 650 and the bottom of the side openings 152; 252; 352; 452; 652 in form cradle, this space including the bottom 156; 256; 356; 456; 656 of the body 150;
250; 350; 450; 650 itself and a portion of the axial housing 151; 251; 351 451; 651.
The retaining means 154; 245; 317; 454; 654 are anyway located so that the surgeon can access it and intervene on them regardless of the connecting rod 30. The surgeon can thus block the kneecap when desired, before operating the patient or during the operation, before bringing the connecting rod 30 into the axial housing 251; 351; 451; 651.
Here, the retaining means 154; 245; 317; 454; 654 are more precisely located between the bottom 156; 256; 356; 456; 656 of the body 150;
250;
350; 450; 650 and the bottoms of lateral openings 152; 252; 352; 452;
652 from body 150; 250; 350; 450; 650.
In the first three embodiments of the spinal implant 100 200; 300 (FIGS. 1 to 18), the locking of the ball joint makes it possible to transform this link ball joint in pivot connection. In this way, when the link patella is blocked, the anchor portions 110; 210; 310 and mounting 120; 220; 320 are free to rotate around a single axis, called the main axis Al.

In these three embodiments, the retaining means 154; 245;
317 are more precisely arranged in such a way that they are capable of to stare said locking member 130 in the locking position only when the axis A2 body 150; 250; 350; 450 is confused with the axis Al of the part anchor 110; 210; 310; 410, which thus constitutes said main axis.
In the fourth and fifth embodiments of the implant spinal 400; 600 (Figures 19 to 26), the locking of the ball joint allows immobilizing the anchoring portions 410; 610 and mounting 420; 620 one by report to the other. In the fourth embodiment, the means of detention

10 454 are also arranged in such a way that they are able to fix said blocking member 430 in the locking position regardless of the orientation of the axis A2 with respect to the axis Al. On the contrary, in the fifth mode of embodiment, the retaining means 654 are arranged in such a way that they are capable of securing said locking member 630 in the locking position only when the axis A2 of the body 650 coincides with the axis Al of the part anchor 610.
Thus, in each of these five embodiments, when no blocking element is retained in the locking position by the means of detention 154; 245; 317; 454; 654, the implant 100; 200; 300; 400; 600 behaves as a poly-axial implant since the ball joint is left free (on said then of the ball joint that is activated - Figures 3, 14, 17, 20 and 25). In however, when the retaining means 154; 245; 317; 454; 654 fix an element of blocking 130; 230; 330; 430; 630 in the locking position, this same implant 100;
200; 300; 400; 600 behaves like a mono-axial implant since the bond ball joint is either completely blocked or locked in pivot connection (it is said so that the ball joint is deactivated - Figures 9, 15, 18, 21 and 26).
Advantageously, the retaining means 154; 245; 317; 454; 654 are further adapted to store the locking member 130; 230; 330; 430;

in a fixed storage position, distinct from the blocking position, in which the ball joint is left active.
With these retaining means 154; 245; 317; 454; 654, the manufacturer of implants can deliver the spinal implant 100; 200; 300; 400; 600 with the element blocking 130; 230; 330; 430; 630 locked in storage position, way that it is not only captive but also easily accessible the surgeon if he wants to disable the ball joint.
Preferably, the first connection means are formed by the head 112; 212; 312; 412; 612 of the anchoring portion 110; 210; 310; 410;

11 which is at least partly spherical to form the male end of the connection patella.
The second connecting means comprise a ring 140;
240; 340; 440; 640 which is housed in the axial housing 151; 251; 351;

651 of the body 150; 250; 350; 450; 650 of the mounting portion 120; 220;
320;
420; 620.
This ring 140; 240; 340; 440; 640 has an inner face 142242; 342; 442; 642 pressing against the head 112; 212; 312; 412; 612 of the anchor portion 110; 210; 310; 410; 610 to form a part at least of the female end of the ball joint.
The ring 140; 240; 340 is preferably longitudinally split on at least part of its length by at least one slot, which imparts a radial elasticity so that it can adapt to the shape of the head 112 ; 212;
312 of the anchoring portion 110; 210; 310.
The ring 140; 240; 340; 440; 640 has an end face 143;
243; 343; 443; 643 which extends to the back of the bottoms of the trained cradles by the two lateral openings 152; 252; 352; 452; 652 of the body 150; 250; 350 ;
450; 650 of the mounting portion 120; 220; 320; 420; 620. Otherwise formula, the ring 140; 240; 340; 440; 640 extends to the introductory opening 155;
255; 355; 455; 655 of the axial housing 151; 251; 351; 451; 651 of the body 150;
250; 350; 450; 650, so that a very small part of his length is located between this introduction opening 155; 255; 355; 455; 655 and the funds two lateral openings 152; 252; 352; 452; 652 of the body 150; 250;
350; 450; 650.
Thus, when the surgeon tightens the locking screw 160; 260; 360;
460; 660 in the tapping provided at the opening opening 155 ;
255; 355; 455; 655 of the axial housing 151; 251; 351; 451; 651, this screw of locking comes to press the connecting rod 30 which itself presses on the rear face 143; 243; 343; 443; 643 of the ring 140; 240; 340; 440;
640, this which blocks any relative movement of the ring relative to the head 112; 212 ;
312; 412; 612 of the anchoring portion 110; 210; 310; 410; 610. Thus, this screw lock 160; 260; 360; 460; 660 makes it possible to immobilize the part of mounting 120; 220; 320; 420; 620 with respect to the anchoring portion 110;
210;
310; 410; 610, so that the axis A2 has the desired orientation by relative to the Al axis.
In the first, second, fourth and fifth embodiments the spinal implant 100; 200; 400; 600, respectively represented on the

12 Figures 2 to 11, 12 to 15, 19 to 22 and 23 to 26, the locking member 130; 230;
430;
630 belongs to the mounting portion 120; 220; 420; 620.
It is more precisely constituted by a ring housed in the housing axial 151; 251; 451; 651 of the body 150; 250; 450; 650 of the part of mounting 120; 220; 420; 620 and realized, like all the other elements of the implant, made of titanium.
In the first, second and fifth embodiments, the element blocking 130; 230; 630 and the anchoring portion 110; 210; 610 have of the abutment faces which, when said locking member 130; 230; 630 is in blocking position, are located in contact with or in the immediate vicinity of the other, which deactivates the ball joint.
More particularly, in the first embodiment of the invention shown in Figures 2 to 11, the head 112 of the anchoring portion 110 present two hemispherical portions 113, 114, of which a hemispherical portion before 113 whose top is connected to the threaded body 111 of the anchoring portion 110, and a rear hemispherical portion 114 whose apex is turned towards the part of 120. This rear hemispherical portion 114 has a diameter less than that of the hemispheric part before 113. This difference in diameters between the two hemispherical parts 113, 114 generates on the head of the anchoring portion 110 an annular shoulder 115 about the axis Al.
Correspondingly, the opening 153 located at the bottom of the axial housing 151 of the body 150 of the mounting portion 120 has a frustoconical shape, either of sphere section (or sphere slice) of equal diameter, at play close to the diameter of the hemispherical portion before 113 of the head 112 of the part 110. This opening 153 thus forms part of said second liaison means. In other words, it forms part of the mouthpiece female of the ball joint.
As shown in FIG. 3, the ring 140 here has a shape substantially tubular, with a cylindrical outer face 144 of revolution around the axis A2 which is bordered, on the side of its front end, by a outer ring 145 of larger diameter. The ring 140 presents by moreover, an inner face in two parts, of which a rear part 141 cylindrical of revolution about this axis A2, and a frustoconical front portion 142 engaged on the rear hemispherical portion 114 of the head 112 of the anchor portion 110.
The locking element 130 has a ring shape and is engaged on the outer face 144 of the ring 140. It is for this purpose split longitudinally, which gives it a radial elasticity to adapt to the

13 outer diameter of the ring 140. The locking element 130 has a face cylindrical interior 133 of revolution about the axis A2. It presents a diameter interior equal, with the clearance, to the outside diameter of the crown 145 of the Ring 140. It is bordered at its rear end by an inner crown 134.
It is thus adapted to slide along the outer face 144 of the ring 140 until a stop position in which its inner ring 134 comes to contact of the outer ring 145 of the ring 140.
In this embodiment of the invention, the retaining means 154 of the blocking element 130 come from forming with the body 150 of the part 120. They are in this case formed by a peripheral rib 154 who extends in the axial housing 151, projecting from the inner face of this housing axial 151, and which here has a symmetry of revolution about the axis A2.
The blocking element 130 has in correspondence, on its face outside, at least one peripheral groove 131, 132 to engage on said peripheral rib 154 to be fixed in the locking position.
As shown in the figures, the locking element 130 presents two detent teeth, which define two peripheral grooves 131, of revolution around the A2 axis. These two peripheral grooves 131, 132 to block the locking element 130 on the peripheral rib 154 of the body 150, optionally, in the storage position (FIG. 3) or blocking (Figure 9).
In the storage position, the front face 135 of the locking element 130 is located at a distance from the annular shoulder 115 of the head 112 of the part anchor 110, so as to leave the ball joint connection activated.
On the other hand, in the blocking position, the front face 135 of the element of blocking 130 is located in contact with or in the immediate vicinity of the shoulder ring 115 of the head 112 of the anchoring portion 110, so as to disable the ball joint. The front face 135 of the locking element 130 and the shoulder ring 115 of the head 112 of the anchoring portion 110 thus form faces of stop, each symmetrical of revolution around axes Al and A2 combined.
By immediate proximity, it is meant that these two thrust faces are located at a distance such that they prevent each other from deflection of the mounting portion 120 relative to the anchoring portion 110 of more than 5 degrees around an axis orthogonal to the main axis Al.
Here, the peripheral groove 154 has a triangle-shaped section rectangle whose hypotenuse is turned towards the back of the body 150 of the part of 120, so that the locking element 130 can be engaged by the rear of the body 150 inside the axial housing 151, in the position of storage

14 then blocking, but that it can not move from the lock position to the storage position, nor be extracted from the body 150. It is thus' perfectly captive.
The establishment of the spinal implant 100 on a vertebra 10, 20 is performed by the surgeon as follows.
When the surgeon takes hold of a new spinal implant 100, this it is preferentially already equipped, on the one hand, with a blocking element 130 disposed in the storage position, and on the other hand, a locking screw screwed into the body 150 of the mounting portion 120.
The surgeon then begins by extracting this locking screw 160 of the body 150. Having access to the reception impression 116 of the head 112 of the anchoring portion 110 of the implant 100, it screws this anchoring portion 110 in the vertebra 10, 20 of the patient.
He then estimates whether or not to disable the ball joint of the implant spinal 100 to better maintain the patient's spine.
If he wishes to leave the connection ball joint active (Figures 4 and 6), he places the stem connection 30 previously bent in the axial housing 151 of the body 150 of the mounting portion 120, through the side openings 152 (Figure 5).
All in now the connecting rod 30 in place, for example using a clamp, he screws then the locking screw 160 in the tapping of the opening introductory 155 of the body 150.
The surgeon then squeezes the locking screw 160 so that the connecting rod 30 bears on the ring 140 in order to immobilize the bond patella.
On the other hand, if the surgeon wishes to disable the kneecap connection to set up the connecting rod 30, he uses a locking key 500 for move the locking member 130 from its storage position to its blocking position.
As shown in FIGS. 7 to 9, such a locking key 500 preferably has a cylindrical body 501, one end cylindrical 503 of smaller diameter to engage in the receiving footprint 116 of the head 112 of the anchoring portion 110, and a tubular portion 502 that extends around of the cylindrical end 503 so as to be able to press on the rear face of the blocking element 130 without interfering with the ring 140.
With this blocking key 500, the surgeon can in a first time to straighten the mounting portion 120 relative to the anchoring portion 110 (FIG. 7) engaging the cylindrical end 503 of the locking key 500 in the receiving impression 116 of the head 112 of the anchoring portion 110.
Al axes and A2 thus merge with the main axis.
The surgeon can then push the blocking member 130 so that that its first peripheral groove 132 disengages from the rib 5 device 154 of the body 150, and that its second peripheral groove 131 engages in turn on said peripheral rib 154 (Figures 8 and 10).
This operation is made possible through the slots of the blocking member 130 and of the ring 140 which allow these two elements to deform elastically radially so that the locking element 130 can pass from the position of 10 storage at the blocking position. At this stage, the ball joint is therefore disabled, such that the anchoring portions 110 and mounting 120 of the implant are linked to each other by a pivot link.
The surgeon then proceeds in a homologous manner to fix the stem of connection 30, engaging the latter in the axial housing 151 of the body

15 and screwing the locking screw 160 into the tapping of the opening 155 of the body 150, so as to immobilize the pivot connection (Figure 11).
In the second embodiment of the invention shown in Figures 12 to 15, the head 212 of the anchoring portion 210 has a shape of hemisphere whose top connects to the threaded body 211 of the part anchor 210, and whose base 213 is turned towards the rear of the part of 220. This base is flat, with the exception of an excavated central part by said reception fingerprint 216.
The ring 240 has in correspondence a shape substantially tubular, with an outer face 244 substantially cylindrical of revolution around the A2 axis and an inner face 242 in two parts, part of which before 248 home head 212 of the anchor portion 210 and a portion back 249 for receiving the locking element 230.
The front portion 248 has a shape of a sphere section of equal diameter, within play, to the diameter of the head 212 of the anchoring portion 210.
This front portion 248 constitutes said second connecting means in this sense that it forms the female end of the ball joint.
The ring 240 is housed in a housing which is formed by the opening 253 located at the bottom of the axial housing 251 of the body 250 of the mounting part 220.
This opening 253 more precisely has a rear portion 259 cylindrical of revolution around the axis A2, which extends to a part before

16 Truncated cone 358 whose apex is turned towards the anchoring portion 210.
at this frustoconical shape, when a connecting rod 30 presses on the face back 243 of the ring 240, the latter sinks into the opening 253 and compresses radially on the head 210 of the anchoring portion, which has the effect to immobilize the ball joint.
In this embodiment of the invention, the retaining means of the blocking element 230 in the blocking and storage position come from formation with the ring 240. They are in this case formed by grooves peripherals 245, 246 located on the rear portion 249 of the inner face 240. These two peripheral grooves 245, 246 have symmetries of revolution about the A2 axis and triangular sections.
The locking element 230 has a puck-like shape inner diameter plate greater than the largest dimension of the footprint of receiving 216 of the head 212 of the anchoring portion 210, and of diameter outside equal, with play, to the diameter of the peripheral grooves 245, 246 of the ring 240.
The locking element 230 is thus adapted to be blocked, optionally, by storage position in the rear peripheral groove 246 (FIG. 14) or in locking position in the front peripheral groove 245 (FIG. 15) of the Ring 240, without interfering with the insertion of an Allen key in the print of receiving 216 of the head 212 of the anchoring portion 210.
The passage of the locking element 230 from one position to the other is thanks to the radial elasticity of the ring 240, which is conferred on it by four slots that extend over part of its length and that are regularly spread on its periphery.
In the storage position, the front face of the locking element 230 is located at a distance from the flat portion of the base 213 of the head 212 of the part anchor 210, so as to leave the ball joint connection activated.
On the other hand, in the blocking position, the front face of the element of blocking 230 is located in contact with the base 213 of the head 212 of the part anchor 210, so as to deactivate the ball joint, so that the anchoring portions 210 and mounting 220 of the implant 200 are related to each other.
the other by a pivot link.
Here, the peripheral grooves 245, 246 have shaped sections of right triangles whose hypotenuses are turned towards the back of the body 250 of the mounting portion 220, so that the locking member 230 can be engaged inside the axial housing 251 by the rear of the body 250 in

17 storage position then blocking but that he can not pass from the position blocking position at the storage position, or being removed from the body 250. It is so perfectly captive.
As shown in FIGS. 13 and 15, the displacement of the element of blocking 230 from its storage position to its blocking position is right here also realized by means of a locking key 500 adapted to come to contact of the rear face of the locking element 230.
As shown in FIG. 15, this blocking key 500 comprises a cylindrical body 504 provided with a thread 505 identical to the thread of the locking screw 260. It is therefore sufficient to screw this lock key 500 in the tapping the insertion opening 255 of the axial housing 251 for move the locking element 230 from its storage position to its position of blocking. The force required to move the locking element 230 is thus scaled down.
In the third embodiment of the spinal implant 300 shown in FIGS. 16 to 18, the locking element 330 belongs to said anchoring part 310.
More particularly, the head 312 of the anchoring portion 310 comprises two hemispherical portions 313, 330 screwed together, one of which part hemispherical front 113 connected by its top to the threaded body 311 of the anchoring portion 310, and a rear hemispherical portion which constitutes said blocking element 330.
The base of the hemispherical part before 113 has for this purpose a threaded stud 317 whose end face has an indentation receipt 316 of a key allen.
The base of the locking element 330 presents in correspondence a threaded bore 337 which is screwed onto this threaded stud 317. The top of this element block 330 has a recess 336 receiving a key allen. As shown in FIGS. 17 and 18, threaded bore 337 and imprint receiver 336 communicate here with each other.
In this embodiment of the invention, the retaining means of the locking element 330 are formed with the anchoring portion 310 and are formed by the threaded stud 317. They are adapted to fix the element of blocking 330 in the storage position when the latter is screwed to the stop on the stud threaded 317, or in blocking position when the latter is partly unscrewed from this threaded stud 317.
In correspondence, the opening 353 located at the bottom of the axial housing 351

18 of the body 350 has a cylindrical rear portion 359 of revolution around of the axis A2, which extends on a front portion 358 in the form of a section of sphere of equal diameter, within play, to the diameter of the forward hemispherical portion the head 312 of the anchoring portion 310.
The front portion 358 of the opening 353 thus forms a part of said second connecting means in that it constitutes a part of the mouthpiece female of the ball joint.
The rear portion 359 of the opening 353 makes it possible to deactivate this ball joint connection when the locking element 330 is partly unscrewed from the stud threaded thread 317 (FIG. 18), so that the anchoring parts 310 and mounting 320 of the implant 300 are connected to each other by a pivot connection.
Indeed, in this position, the circular contours of the bases of the two hemispherical portions 313, 330 of the head 312 of the anchoring portion 310 extend in the cylindrical rear portion 359 of the opening 353, which blocked the ball joint connection in pivot connection.
As shown in FIG. 16, the ring 340 presents here a substantially tubular shape, with a cylindrical outer face 344 of revolution around the axis A2 of equal diameter, with the play, the diameter of the axial housing 351. It has an inner face in two parts, of which a rear portion 341 cylindrical of revolution about this axis A2, and a part before frustoconical 342 engaged on the blocking element 330.
The establishment of the spinal implant 300 on a vertebra 10, 20 is performed by the surgeon as follows.
After extracting the locking screw 360 from the body 350 of the part of assembly 320, the surgeon who has access to the receipt impression 316 of the head 312 of the anchoring portion 310 of the implant 300 screws this anchoring portion in the vertebra 10, 20 of the patient.
He then estimates whether or not to disable the ball joint of the implant spinal 300 If he wishes to leave the connection ball joint active (Figure 17), he ensures that the locking element 330 is screwed as far as the stop on the threaded stud 317, in position storage. He then places the connecting rod 30 previously bent into the axial housing 351 of the body 350, through the lateral openings 352.
Then he screw the locking screw 360 into the tapping of the opening introduction 355 of the body 350, and tightens the locking screw 360 so that the rod of link 30 bears on the ring 340 and thus immobilizes the connection patella.
On the other hand, if the surgeon wishes to disable the kneecap connection, he uses

19 a simple allen key to move the locking element 330 from its position of storage to its blocking position.
The surgeon unscrews for this purpose the locking element 330 on a part the length of the threaded stud 317 (FIG. 18), so that the element of blocking 330 extends for the most part in the axial housing 351, in neighboring the bottoms of the lateral openings 352 of the body 350. In this way, the head of the anchoring portion 310 is locked in pivot connection relative to the part of mounting 320.
The surgeon then proceeds in an identical manner to fix the stem of connection 30, by engaging the latter in the axial housing 351 and in screwing the locking screw 360 in the tapping of the opening 355 of the body 350, so as to immobilize the pivot connection (Figure 11).
In the fourth embodiment of the invention shown in FIGS. 19 to 22, the head 412 of the anchoring portion 410 is spherical and is engaged in opening 453 provided in the bottom 456 of the 450 body. It is maintained in this opening 453 by the ring 440.
The ring 440 has for this purpose two parts, including a rear part 445 against which the connecting rod 30 bears, and a part 444 frustoconical front provided to press the head 412 of the part anchor 410. The inner face of the front portion 446 of the ring 440 has more precisely a form of sphere section of equal diameter, with play, at diameter of the head 412 of the anchoring portion 410. This front portion 446 of the ring 440 then belongs to said second connecting means in this sense what forms part of the female end of the ball joint.
The ring 440 is housed in the axial housing 451, close to the bottom 456 of the body 450 of the mounting portion 420.
In this embodiment of the invention, the retaining means 454 of the blocking element 430 in the blocking and storage position come from training with the body 450. They are in this case formed by a thread 454 who extends on the cylindrical inner face of the axial housing 451, from the edge rear of the opening 453 provided in the bottom 456 of the body 450, to the opening 455 engagement of the body 450.
The locking element 430 has a ring shape of inner diameter greater than the largest dimension of the footprint of receiving 416 of the head 412 of the anchoring portion 410, and of diameter outside slightly smaller than the diameter of the axial housing 451. The outer face of this blocking element 430 is equipped with a thread 434 allowing the element of blocking 430 to be screwed into the thread 454 provided in the axial housing 451, to near the bottom 456 of the body 450.
The inner face of this locking element 430 has a part 435 cylindrical rear of revolution about the axis A2, of diameter equal to 5 diameter of the tubular rear portion 445 of the ring 440, and a portion before 436 frustoconical, able to be applied against the outer face of the front part frustoconical ring 440.
The locking element 230 is thus adapted to be screwed into the thread 454 of the axial housing 451, sliding along the rear portion 445 tubular 10 of the ring 440, to be blocked at choice in the storage position (FIG.

20) or in blocking position (Figure 21).
In the storage position, the locking element 430 is screwed into the thread 454 of the axial housing 451 with a low tightening torque, way to leave the ball joint activated. The surgeon can thus incline at will the A2 axis 15 of the body 450 of the mounting portion 420 with respect to the axis Al of the part anchor 410.
In contrast, in the locking position, the blocking element 430 is screwed in the thread 454 of the axial housing 451 with a tightening torque important, so as to disable the ball joint. In this position, the parties anchor 410 and mounting 420 of the implant 400 are immobilized relative to each other.
at the other.
As shown in FIG. 21, the anchor portions 410 and 420 are locked in an aligned position (the axes A1 and A2 are combined). Alternatively, the surgeon can also immobilize the parts anchoring 410 and mounting 420 so that they are immobilized in an inclined position relative to each other.
To facilitate the screwing of the locking element 430 in the thread 454 of the axial housing 451, this blocking element 430 has four indentations 437 that extend recess into its back side and that are regularly spread on its periphery.
Locking key 510 (FIGS. 19 and 22) used to screw this element block 430 comprises in correspondence a cylindrical body 512, of diameter less than the diameter of the axial housing 451, equipped at its end before a peripheral ring 514 provided with four lugs 511 to engage in the indentations 437 of the locking element 430.
This locking key 510 is here equipped with a nipple before 513 more small diameter, which is located in the center of peripheral ring 514 and which

21 ensures that the locking of the ball joint is only when the anchoring portions 410 and mounting 420 of the implant 400 are aligned.
With this locking key 510, the surgeon can in a first time to straighten the mounting portion 420 of the implant 400 relative to its part anchoring 410 by engaging the stud before 513 of the locking key 510 in the receiving fingerprint 416 of the head 412 of the anchoring portion 410.
The surgeon can then screw the locking element 430 into engagement the pins 511 of the blocking key 510 in the notches 437 of the element of blocking 430, and turning the locking key 510 to lock the ring against the head 412 of the anchoring portion 410, in order to immobilize the connection patella.
Alternatively, it may also be provided that the locking key is devoid of front nipple. In this way, the locking key can also be used to block the ball joint in a position in which the anchoring portions 410 and mounting 420 of the implant 400 are inclined one by report to the other.
In the fifth embodiment of the invention shown in Figures 23 to 26, the head 612 of the anchoring portion 610 has two parts hemispherical diameters to delimit between them a shoulder ring 615 around the axis Al. These two hemispherical parts are here grooved to increase their adhesion.
In correspondence, the opening 653 located at the bottom of the axial housing 651 of the body 650 of the mounting part 620 has a shape of a section of sphere to form the female end of the ball joint.
As shown in FIG. 25, the ring 640 has a shape substantially tubular. It is lined, on the side of its front end, by a outer crown. It presents internally, on the side of its end before, a spherical portion 642 engaged on the rear hemispherical portion of the head 612 of the anchoring portion 610.
The locking element 630 has a ring shape. he has, on the side of its rear end, a groove 635 of inner diameter equal, with play, to the outer diameter of the ring 640.
This blocking element 630 can thus be fitted onto the ring 640 of such way that it is adapted to slide along the outer face of the ring to an abutment position in which its groove 635 comes into contact with the outer ring of the ring 640.
In this embodiment of the invention, the retaining means 654 of the blocking element 630 come from forming with the 650 body of the part

22 620. They include in this case a tapping which extends into the axial housing 651.
The blocking element 630 presents in correspondence, on its face outer thread 631 to be screwed into the thread 654 of the body 650.
As shown in the figures, the retaining means 654 of blocking element 630 furthermore comprise a peripheral groove situated at the back of the tapping, which hosts a circlip 670 of maintaining the element of blocking 630 in the axial housing 651 of the body 650. This circlip is in species formed by a simple split ring.
This circlip 670 thus makes it possible to block the locking element 630 in storage position (Figure 25) when the thread 631 of the element of blocking 630 is unscrewed from the tapping of the body 650. In this storage position, the front face of the locking element 630 is located away from the shoulder ring 615 of the head 612 of the anchoring portion 610, so as to leave the ball joint connection activated.
On the other hand, in the blocking position, when the locking element 630 is screwed into the tapping 654 of the body 650, the front face of the blocking 630 is located in contact with the annular shoulder 615 of the head 612 of the anchoring portion 610, so as to deactivate the ball joint. In this position, the body 650 is held in a fixed position relative to the part anchor 610.
The placement of the spinal implant 600 on a vertebra 10, 20 is performed by the surgeon using a locking tool 700 of the type of the one shown in Figure 24.
Such a blocking tool 700 here comprises an inner rod 710 mounted mobile in rotation in an outer tube 720.
The outer tube 720 has, on the side of its front end, two side wings 721 of identical shapes, in negative, to those of the openings 652 of the body 650. This outer tube 720 thus allows, during the installation of the spinal implant 600 on a vertebra 10, 20, de maintain the body 650 of the implant in a fixed position relative to the vertebrae.
The inner rod 710 has four lugs 711 in form crenellations that rise from its front end to engage in of the notches provided in correspondence on the rear end of the element of 630. This inner rod 710 allows, during the installation of the spinal implant 600 on a vertebra 10, 20, to screw the element of blocking 630 in the bore of the body 650 of the implant, so as to place the element of blocking

23 630 in the locked position.
This inner rod 710 is further equipped with a front pin 712 for straightening the mounting portion 620 in the axis of the portion 610 of the spinal implant 600 before the locking element 630 does not immobilize the ball joint.

Claims (19)

A spinal implant (100) comprising:
an anchoring portion (110) to a vertebra (10, 20), comprising first connecting means (112), and a mounting part (120) comprising, on the one hand, internally a axial housing (151) opening outwards through two lateral openings (152) facing and shaped cradles to accommodate transversely a stem link (30), the axial housing (151) being delimited on the side of the part anchor (110) by a bottom (156), and secondly, second means for bond (140, 153) which cooperate with said first link means (112) for forming a ball joint connection between said anchoring portion (110) and said portion of mounting (120), characterized in that it comprises retaining means (154) which are located in a space between the bottom of the cradles formed by the said two lateral openings (152) and the bottom (156) of the axial housing (151), and who are adapted to fix a locking element (130), distinct from the second means of link (140, 153) in a fixed locking position in which the bond ball joint formed by said first and second connecting means (112, 140, 153) is locked to make said anchoring (110) and mounting portions (120) fixed in rotation with respect to each other around at least two axes orthogonal (A3, A4). 2. Spinal implant (100) according to the preceding claim, wherein said retaining means (154) is adapted to store said element of blocking (130) in a fixed storage position, distinct from the position of blocking wherein the ball joint formed by said first and second means of link (112, 140, 153) is left free. 3. Spinal implant (100) according to one of the preceding claims, wherein, when the ball joint is locked, said anchoring portions (110) and mounting (120) are fixed relative to each other. 4. Spinal implant (100) according to one of claims 1 and 2, in which, when the ball joint is locked, said anchoring parts (110) and mounting (120) are free to pivot about a single main axis (A1), orthogonal to said two orthogonal axes (A3, A4). 5. Spinal implant (100) according to one of the preceding claims, wherein said anchoring portion (110) having a threaded body (111) extending along a first axis (A1), and said axial housing (151) extending along a second axis (A2), said retaining means (154) are arranged such that they are capable of fixing said locking element (130) in locking position only when said second axis (A2) coincides with said first axis (A1). 6. spinal implant (100) according to one of the preceding claims, wherein said first connecting means comprises a head (112) at less in part spherical and wherein said second connecting means comprise a ring (140) whose inner face (142) bears against said head (112). 7. Spinal implant (100) according to the preceding claim, wherein said axial housing (151) opens outwards through two openings lateral (152) facing and in the form of cradles, and wherein said ring (140) has an end face (143) which extends above the bottoms of the cradles formed by said two lateral openings (152). 8. Spinal implant (100) according to one of the preceding claims, wherein said axial housing (151) opens outwardly away from the background (156) by an insertion opening (155) and said mounting portion (120) comprises, close to this introduction opening (155), a thread (154) who cooperates with a thread (162) complementary to a locking screw (160) for immobilizing said connecting rod (30) and said ball joint. 9. Spinal implant (100) according to one of the preceding claims, having a locking element (130) adapted to cooperate with said means retainer (154) to be fixed in said locking position. . 10. Spinal implant (300) according to the preceding claim, in wherein said locking member (330) belongs to said anchor portion (310). The spinal implant (300) according to claims 6 and 10, wherein the head (312) of the anchoring portion (310) has two parts (313, 330) screwed one on the other, a first part of which constitutes said blocking element (330). 12. Spinal implant (300) according to the preceding claim, in which the bottom (356) which delimits the axial housing (351) on the side of the part anchor (310) has an opening (353) through which said axial housing (351) opens outward, this opening (353) having a portion cylindrical which extends on a spherical or conical part, and in which said locking element (330), when in the locking position, is located at contact of said cylindrical portion of the opening (353). The spinal implant (100; 200; 400) according to claim 9, wherein wherein said locking member (130; 230; 430) belongs to said portion of mounting (120; 220; 420). 14. Spinal implant (100) according to the preceding claim, in wherein said locking member (130) is constituted by a ring. 15. Spinal implant (100) according to one of the two claims in which said blocking element (130) and said part anchor (110) have abutment faces (115, 135) which, when said blocking (130) is in the locked position, is in contact with or proximity immediately from each other. 16. Spinal implant (100) according to one of claims 13 to 15, in which, said mounting means (120) having a body (150) which comprises said bottom (156) and which defines said axial housing (151), said means for detention (154) are formed with the body (150) and said blocking member (130) has an outer face engaged in said retaining means (154). 17. Spinal implant (100) according to the preceding claim, in wherein said retaining means (154) comprises a peripheral ridge who extends in said axial housing (151), projecting from the inner face of the body (150) which defines this axial housing. The spinal implant (400) according to claim 16, wherein said retaining means comprises a thread (454) extending on the face indoor the body (450) defining said axial housing (451). 19. Spinal implant (200) according to one of claims 13 to 15, in which, said mounting means (220) having a ring (240) engaged in said axial housing (251), said retaining means (254) come from forming with said ring (240) and said blocking member (230) a outer face engaged in said retaining means (254).